1. Field of the Invention
The present invention generally relates to a solid state image pickup apparatus, and particularly relates to a technique effectively applicable to a solid state image pickup apparatus, for example, of the type in which a picture signal formed by a photoelectric conversion element is taken out on the basis of a selection signal formed by a horizontal and a vertical shift register.
2. Description of the Prior Art
Solid state image pickup devices constituted by a combination of photo-diodes and switch MOS FETs are well known. One example of such a solid state image pickup apparatus is described for example, in Japanese Patent Unexamined Publication No. 59-63892(1984).
The inventors of this application have thought the use of the foregoing solid state image pickup apparatus for recognition of patterns such as characters, marks, figures, and the like. The foregoing solid state image pickup apparatus, however, has been developed mainly as a camera for a television. Therefore, this apparatus suffers from an inconvenience that a full picture signal for a television screen is produced to thereby spoil a high-speed operation even when pattern recognition is performed within a relatively narrow range. In other words,a high-speed operation cannot be performed in spite of the fact that only a narrow range is involved. Therefore, it is considered that a solid state image pickup apparatus should be designed which is exclusive to pattern recognition within a relatively narrow range. Accordingly, it may be considered to develop such solid state image pickup apparatus for exclusive use. However, in view of the variety of use typically envisioned for pickup devices, the solid state image pickup apparatus for exclusive are grouped into many kinds, each in small quantities, resulting in an increase in cost for development as well as for manufacture.